000 WTPZ42 KNHC 221438 TCDEP2 TROPICAL STORM BUD DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL EP022012 800 AM PDT TUE MAY 22 2012 WITHOUT RECENT MICROWAVE DATA...IT HAS BEEN DIFFICULT TO LOCATE THE CENTER OF BUD. THE INITIAL POSITION IS BASED PRIMARILY ON AN EXTRAPOLATION OF THE PREVIOUS FORECAST...WHICH DOES KEEP THE CENTER ALONG THE EASTERN EDGE OF THE DEEP CONVECTION. MANUAL AND AUTOMATED DVORAK ESTIMATES ALL YIELD AN INTENSITY AROUND 35 KT...AND THAT WILL REMAIN THE INTENSITY ON THIS ADVISORY. THE INITIAL MOTION IS 300/11 KT. THE MID-LEVEL RIDGE TO THE NORTHWEST OF THE CYCLONE IS RETREATING WESTWARD...AND BUD IS EXPECTED TO TURN NORTHWESTWARD AND THEN NORTHWARD THROUGH THURSDAY. THE OFFICIAL FORECAST IS EMBEDDED WITHIN THE TIGHT CLUSTER OF TRACK GUIDANCE THROUGH 36 HOURS...BUT THERE IS MORE DIVERGENCE IN THE MODELS FROM 48 HOURS AND BEYOND. BUD SHOULD STILL TURN NORTHEASTWARD BY DAY 3 WHEN IT FEELS THE INFLUENCE OF A DEEPENING MID-LATITUDE TROUGH ALONG THE U.S. PACIFIC COAST...BUT SEVERAL OF THE GLOBAL MODELS SUGGEST THAT THE TROUGH WILL LIFT NORTHWARD AND A MID-LEVEL RIDGE WILL BUILD ACROSS THE GULF OF MEXICO...PREVENTING BUD FROM REACHING THE MEXICAN COAST. THE ECMWF IS THE BIGGEST OUTLIER ON DAY 3...BEING SLOWER AND FARTHER SOUTH THAN THE MAIN CLUSTER OF MODELS...BUT THE REST OF THE GLOBAL MODELS ARE TRENDING TOWARDS BUD STALLING BEFORE REACHING THE COAST OF MEXICO AT DAYS 4 AND 5. THE NHC TRACK FORECAST FOLLOWS THIS SCENARIO AND IS BASED ON A CONSENSUS OF THE GFS AND ECMWF MODELS ON THOSE DAYS. APPROXIMATELY 10-15 KT OF DEEP-LAYER EASTERLY SHEAR CONTINUES TO AFFECT BUD. UPPER-LEVEL WINDS ARE EXPECTED TO BE MORE CONDUCIVE FOR INTENSIFICATION THROUGH DAY 3...BUT THE OCEANIC HEAT CONTENT WILL BE DECREASING DURING THAT PERIOD AS THE STORM MOVES FARTHER NORTH. THE STATISTICAL GUIDANCE IN PARTICULAR CONTINUES TO TONE DOWN THE AMOUNT OF STRENGTHENING...AND THE SHIPS DIAGNOSTICS SHOW RELATIVELY WARM UPPER LEVELS OF THE ATMOSPHERE AS THE BIGGEST LIMITING FACTOR. THEREFORE...THE PEAK INTENSITY SHOWN IN THE NHC FORECAST IS A LITTLE LOWER THAN THE PREVIOUS FORECAST BUT STILL SHOWS BUD REACHING HURRICANE STRENGTH IN 2 TO 3 DAYS. EVEN THOUGH THE FORECAST TRENDS DEPICT A WEAKER CYCLONE STAYING OFF THE MEXICAN COAST...EFFECTS FROM BUD COULD STILL REACH THE COAST. WIND SPEED PROBABILITIES BASED ON NHC 5-YEAR MEAN ERRORS STILL SHOW A 1 IN 3 CHANCE OF TROPICAL-STORM-FORCE WINDS AT COASTAL LOCATIONS IN THE MEXICAN STATES OF JALISCO...COLIMA...AND MICHOACAN. FORECAST POSITIONS AND MAX WINDS INIT 22/1500Z 11.1N 104.0W 35 KT 40 MPH 12H 23/0000Z 11.9N 105.2W 40 KT 45 MPH 24H 23/1200Z 12.8N 106.4W 50 KT 60 MPH 36H 24/0000Z 13.7N 106.9W 60 KT 70 MPH 48H 24/1200Z 14.6N 106.6W 70 KT 80 MPH 72H 25/1200Z 16.5N 105.5W 70 KT 80 MPH 96H 26/1200Z 18.0N 104.5W 55 KT 65 MPH 120H 27/1200Z 18.0N 105.0W 45 KT 50 MPH $$ FORECASTER BERG